1,4-diaminobutane (also referred to as putrescine) may be produced by using a chemical method or a biological method. The chemical method involves using a toxic material such as hydrogen cyanide or an expensive reaction catalyst. The biological method may include producing 1,4-diaminobutane by culturing a microorganism that produces 1,4-diaminobutane and refining the 1,4-diaminobutane from a fermented broth. Therefore, the biological method is environment-friendly, compared to the chemical method and does not use an expensive catalyst.
However, in the conventional biological method of producing 1,4-diaminobutane, the fermented broth includes a sulfate of 1,4-diaminobutane, and thus an alkali compound is added thereto to purify the sulfate, a large amount of by-products are produced, and additional purifying process of the by-products is needed.
Therefore, a simple and economic method that does not require addition of an alkali compound during the purifying process and that may reduce production of by-products is needed.